tedious-connection-pool

A connection pool for tedious.

Installation

npm install mhingston/tedious-connection-pool

Description

The API is almost identical to the official tedious-connection-pool. Rather than creating a connection and then closing it when finished, you acquire a connection from the pool and release it when finished.

Once the Tedious Connection object has been acquired, the tedious API can be used with the connection as normal.

Example (callback)

var ConnectionPool = require('tedious-connection-pool');
var Request = require('tedious').Request;

var poolConfig = {
    min: 2,
    max: 4,
    log: true
};

var connectionConfig = {
    userName: 'login',
    password: 'password',
    server: 'localhost'
};

//create the pool
var pool = new ConnectionPool(poolConfig, connectionConfig);

//acquire a connection
pool.acquire(function (error, connection) {
    if (error) {
        console.error(error);
        return;
    }

    //use the connection as normal
    var request = new Request('select 42', function(error, rowCount) {
        if (error) {
            console.error(error);
            return;
        }

        console.log('rowCount: ' + rowCount);

        //release the connection back to the pool when finished
        connection.release();
    });

    request.on('row', function(columns) {
        console.log('value: ' + columns[0].value);
    });

    connection.execSql(request);
});

Example (promise)

var ConnectionPool = require('tedious-connection-pool');
var Request = require('tedious').Request;

var poolConfig = {
    min: 2,
    max: 4,
    log: true
};

var connectionConfig = {
    userName: 'login',
    password: 'password',
    server: 'localhost'
};

//create the pool
var pool = new ConnectionPool(poolConfig, connectionConfig);

//acquire a connection
pool.acquire()
.then(function (connection) {
    //use the connection as normal
    var request = new Request('select 42', function(error, rowCount) {
        if (error) {
            console.error(error);
            return;
        }

        console.log('rowCount: ' + rowCount);

        //release the connection back to the pool when finished
        connection.release();
    });

    request.on('row', function(columns) {
        console.log('value: ' + columns[0].value);
    });

    connection.execSql(request);
})
.catch(function (error) {
    console.error(error);
});

When you are finished with the pool, you can drain it (close all connections).

pool.drain();

Class: ConnectionPool

new ConnectionPool(poolConfig, connectionConfig)

• poolConfig {Object} the pool configuration object

  • min {Number} The minimun of connections there can be in the pool. Default = 10
  • max {Number} The maximum number of connections there can be in the pool. Default = 50
  • idleTimeout {Number} The number of milliseconds before closing an unused connection. Default = 30000
  • acquireTimeout {Number} The number of milliseconds to wait for a connection, before returning an error. Default = 60000
  • log {Boolean|Function} Set to true to have debug log written to the console or pass a function to receive the log messages. Default = false

• connectionConfig {Object} The same configuration that would be used to create a tedious Connection.

connectionPool.acquire(callback)

Acquire a Tedious Connection object from the pool. This method returns a promise, but you can use a callback function if you prefer.

• callback(error, connection) {Function} Callback function
• error {Object} Object containing an error that occurred whilst trying to acquire a connection, otherwise null.
• connection {Object} A Connection

connectionPool.drain()

Close all pooled connections and stop making new ones. The pool should be discarded after it has been drained.

Class: Connection

The following method is added to the Tedious Connection object.

Connection.release()

Release the connection back into the pool to be used again.